While the data was previously available through the Europeana website, dedicating it to the public domain multiplies its usability. From the press release:

This release, which is by far the largest one-time dedication of cultural data to the public domain using CC0 offers a new boost to the digital economy, providing electronic entrepreneurs with opportunities to create innovative apps and games for tablets and smartphones and to create new web services and portals.

Europeana’s move to CC0 is a step change in open data access. Releasing data from across the memory organisations of every EU country sets an important new international precedent, a decisive move away from the world of closed and controlled data.

Last week we tweeted that Cologne-based libraries had released 5.4 million bibliographic records under CC0. This is tremendous news, as “libraries have been involved with the Open Access movement for a long time.” From the press release,

Rolf Thiele, deputy director of the USB Cologne, states: “Libraries appreciate the Open Access movement because they themselves feel obliged to provide access to knowledge without barriers. Providing this kind of access for bibliographic data, thus applying the idea of Open Access to their own products, has been disregarded until now. Up to this point, it was not possible to download library catalogues as a whole. This will now be possible. We are taking a first step towards a worldwide visibility of library holdings on the internet.”
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“In times in which publishers and some library organisations see data primarily as a source of capital, it is important to stick up for the traditional duty of libraries and librarians. Libraries have always strived to make large amounts of knowledge accessible to as many people as possible, with the lowest restrictions possible,” said Silke Schomburg, deputy director of the hbz. “Furthermore libraries are funded by the public. And what is publicly financed should be made available to the public without restrictions,” she continued.

With so much library data now in the public domain, there emerges greater potential synergy for libraries and the Semantic Web:

The North Rhine-Westphalian Library Service Center has recently begun evaluating the possibilities to transform data from library catalogs in such a way that it can become a part of the emerging Semantic Web. The liberalization of bibliographic data provides the legal background to perform this transformation in a cooperative, open, and transparent way. Currently there are discussions with other member libraries of the hbz library network to publish their data. Moreover, “Open Data” and “Semantic Web” are topics that are gaining perception in the international library world.